 /*******************************************************************************
  * Copyright (c) 2000, 2007 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.handlers;

 import java.util.Map ;

 import org.eclipse.core.commands.AbstractHandler;
 import org.eclipse.core.commands.ExecutionEvent;
 import org.eclipse.core.commands.ExecutionException;
 import org.eclipse.jface.window.Window;
 import org.eclipse.ui.IViewPart;
 import org.eclipse.ui.IViewReference;
 import org.eclipse.ui.IWorkbenchPage;
 import org.eclipse.ui.IWorkbenchWindow;
 import org.eclipse.ui.PartInitException;
 import org.eclipse.ui.internal.FastViewBar;
 import org.eclipse.ui.internal.Perspective;
 import org.eclipse.ui.internal.WorkbenchMessages;
 import org.eclipse.ui.internal.WorkbenchPage;
 import org.eclipse.ui.internal.WorkbenchPlugin;
 import org.eclipse.ui.internal.dialogs.ShowViewDialog;
 import org.eclipse.ui.internal.misc.StatusUtil;
 import org.eclipse.ui.statushandlers.StatusManager;
 import org.eclipse.ui.views.IViewDescriptor;

 /**
  * Shows the given view. If no view is specified in the parameters, then this
  * opens the view selection dialog.
  *
  * @since 3.1
  */
 public final class ShowViewHandler extends AbstractHandler {

     /**
      * The name of the parameter providing the view identifier.
      */
     private static final String PARAMETER_NAME_VIEW_ID = "org.eclipse.ui.views.showView.viewId"; //$NON-NLS-1$
 private boolean makeFast = false;
     private static final String PARAMETER_MAKE_FAST = "org.eclipse.ui.views.showView.makeFast"; //$NON-NLS-1$

     /**
      * Creates a new ShowViewHandler that will open the view in its default location.
      */
     public ShowViewHandler() {
     }
     
     /**
      * Creates a new ShowViewHandler that will optionally force the view to become
      * a fast view.
      *
      * @param makeFast if true, the view will be moved to the fast view bar (even if it already
      * exists elsewhere). If false, the view will be shown in its default location. Calling with
      * false is equivalent to using the default constructor.
      */
     public ShowViewHandler(boolean makeFast) {
         this.makeFast = makeFast;
     }
     
     public final Object execute(final ExecutionEvent event)
             throws ExecutionException {
         IWorkbenchWindow window = HandlerUtil
                 .getActiveWorkbenchWindowChecked(event);
         // Get the view identifier, if any.
 final Map parameters = event.getParameters();
         final Object value = parameters.get(PARAMETER_NAME_VIEW_ID);
         makeFast = "true".equals(parameters.get(PARAMETER_MAKE_FAST)); //$NON-NLS-1$

         if (value == null) {
             openOther(window);
         } else {
             try {
                 openView((String ) value, window);
             } catch (PartInitException e) {
                 throw new ExecutionException("Part could not be initialized", e); //$NON-NLS-1$
 }
         }

         return null;
     }

     /**
      * Opens a view selection dialog, allowing the user to chose a view.
      */
     private final void openOther(final IWorkbenchWindow window) {
         final IWorkbenchPage page = window.getActivePage();
         if (page == null) {
             return;
         }
         
         final ShowViewDialog dialog = new ShowViewDialog(window,
                 WorkbenchPlugin.getDefault().getViewRegistry());
         dialog.open();
         
         if (dialog.getReturnCode() == Window.CANCEL) {
             return;
         }
         
         final IViewDescriptor[] descriptors = dialog.getSelection();
         for (int i = 0; i < descriptors.length; ++i) {
             try {
                 openView(descriptors[i].getId(), window);
             } catch (PartInitException e) {
                 StatusUtil.handleStatus(e.getStatus(),
                         WorkbenchMessages.ShowView_errorTitle
                                 + ": " + e.getMessage(), //$NON-NLS-1$
 StatusManager.SHOW);
             }
         }
     }

     /**
      * Opens the view with the given identifier.
      *
      * @param viewId
      * The view to open; must not be <code>null</code>
      * @throws PartInitException
      * If the part could not be initialized.
      */
     private final void openView(final String viewId,
             final IWorkbenchWindow activeWorkbenchWindow)
             throws PartInitException {

         final IWorkbenchPage activePage = activeWorkbenchWindow.getActivePage();
         if (activePage == null) {
             return;
         }

         if (makeFast) {
             WorkbenchPage wp = (WorkbenchPage) activePage;
             Perspective persp = wp.getActivePerspective();

             // If we're making a fast view then use the new mechanism directly
 boolean useNewMinMax = Perspective.useNewMinMax(persp);
             if (useNewMinMax) {
                 IViewReference ref = persp.getViewReference(viewId, null);
                 if (ref == null)
                     return;

                 persp.getFastViewManager().addViewReference(FastViewBar.FASTVIEWBAR_ID, -1, ref, true);
                 wp.activate(ref.getPart(true));
                 
                 return;
             }
             
             IViewReference ref = wp.findViewReference(viewId);
             
             if (ref == null) {
                 IViewPart part = wp.showView(viewId, null, IWorkbenchPage.VIEW_CREATE);
                 ref = (IViewReference)wp.getReference(part);
             }
             
             if (!wp.isFastView(ref)) {
                 wp.addFastView(ref);
             }
             wp.activate(ref.getPart(true));
         } else {
             activePage.showView(viewId);
         }
         
     }
 }

